James, the World and Olympic 400 metres champion from Grenada, held off a challenge to win his event in a world leading time of 43.96 seconds.

The 20-year-old Grenadian ran a controlled first 150m before accelerating ahead of American LaShawn Merritt to win and broke the 44-second barrier for the second time in his career.

"Today, in comparison to previous races, I had a bit better 200m. I couldn't let LaShawn go in the early stages of the race otherwise it would have been too much to beat him," said James.

The victory will give James bragging rights to retain his title at the IAAF World Championships in Athletics in Moscow in August. Prior to Saturday's event, both athletes shared a victory in the Diamond League campaign.

Americans Tony McQuay (44.84) and David Verburg (44.97) and 37 year-old Christopher Brown of the Bahamas (45.24) completed the top five finishers.

James won the Olympic title in London in 43.94, becoming the first person to run sub-44 since Merritt broke the mark in 2007 with his 43.96 in Osaka, Japan, and behind another American Jeremy Wariner's 43.45.

Bolt was made to work hard for a victory in the half-lap as compatriot Warren Weir stayed with him into the top bend before the world record-holder pulled away to win in a world leading and meet record of 19.73.

Weir stayed below the 20-second barrier with 19.92 and Frenchman Christophe LeMaitre finished third in 20.07.

"I lost one 100 metres and a lot of people are making a big deal out of it, and it doesn't really bother me," the Jamaican said in reference to his defeat by Justin Gatlin in Rome last month.

"I am a championship person. I'm not worried, as long as I'm in great shape."

Jamaicans Jason Young (20.12, SB) and Nickel Ashmeade (20.21) completed the top five finishers.

Fraser-Pryce shrugged off the disappointment of Birmingham to edge Blessing Okagbare of Nigeria to win the Women's 100 metres in a season's best 10.92. She lost to the Nigerian over the 200m about a week ago but took the shorter distance to Okagbare's 10.93.

"Today it was not the best race technically but I still managed to win," said Fraser-Pryce.

"I did not feel Blessing coming; I just ran my own race."

Forbes was lone Caribbean winner in the field events when he leaped 8.11m on just his second attempt to win the Men's Long Jump among a talented field including Chris Tomlinson of Great Britain (8.08) and Louis Tsatoumas of Greece (8.02).